Formation of a capacitor using a sacrificial layer

ABSTRACT

Methods, apparatuses, and systems related to forming a capacitor using a sacrificial material are described. An example method includes forming a first silicate material on a substrate. The method further includes forming a first nitride material on the first silicate material. The method further includes forming a second silicate material on the first nitride material. The method further includes forming a second nitride material on the second silicate material. The method further includes forming a sacrificial material on the second nitride material. The method further includes forming a column of capacitor material through the first silicate material, the first nitride material, the second silicate material, the second nitride material, and the sacrificial material. The method further includes removing the sacrificial material to expose a top portion of the capacitor material.

TECHNICAL FIELD

The present disclosure relates generally to semiconductor devices andmethods, and more particularly to formation of a capacitor using asacrificial layer.

BACKGROUND

Memory devices are typically provided as internal, semiconductor,integrated circuits in computers or other electronic devices. There aremany different types of memory, including random-access memory (RAM),read only memory (ROM), dynamic random access memory (DRAM), staticrandom access memory (SRAM), synchronous dynamic random access memory(SDRAM), ferroelectric random access memory (FeRAM), magnetic randomaccess memory (MRAM), resistive random access memory (ReRAM), and flashmemory, among others. Some types of memory devices may be non-volatilememory (e.g., ReRAM) and may be used for a wide range of electronicapplications in need of high memory densities, high reliability, and lowpower consumption. Volatile memory cells (e.g., DRAM cells) requirepower to retain their stored data state (e.g., via a refresh process),as opposed to non-volatile memory cells (e.g., flash memory cells),which retain their stored state in the absence of power. However,various volatile memory cells, such as DRAM cells may be operated (e.g.,programmed, read, erased, etc.) faster than various non-volatile memorycells, such as flash memory cells.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-6 illustrate cross-sectional views of a portion of an examplememory device at stages of an example fabrication sequence for formationof a plurality of pillars of capacitors using a sacrificial layer inaccordance with a number of embodiments of the present disclosure.

FIGS. 7-9 are flow diagrams of example methods for fabrication sequencefor formation of a plurality of pillars of capacitors using asacrificial layer in accordance with a number of embodiments of thepresent disclosure.

DETAILED DESCRIPTION

Various types of memory devices (e.g., those that include volatile ornon-volatile memory cells) may include rectilinear trenches and/orround, square, oblong, etc., cavities that may be formed into a sidewallstructural material as openings. Such openings may contain, or beassociated with, various materials that contribute to data access,storage, and/or processing, or to various support structures, on thememory device. As an example, capacitor material may be deposited intothese openings to provide the data access, storage, and/or processing.

In order to increase the capacitance of a cell of the memory device, asurface area of the capacitor material formed into a column can beincreased by increasing the height of the capacitor material columnwithin the opening. However, due to possible gap margins and smallerpitch, increasing the height of a capacitor column can increase the riskof bending and wobbling of the capacitor column, causing possibleshorts.

In order to mitigate this issue, a method for forming a capacitor usinga sacrificial layer is described further below. As an example, acapacitor can include a mid lattice portion and top lattice portionincluding oxides (TEOS and BPSG) in between the mid lattice and toplattice portions. This dual lattice structure can include an amount ofrecess material (e.g., a sacrificial layer of Nitride or Oxide) abovethe top lattice. Positioning a sacrificial layer above a top lattice canreduce bending of the capacitors by reducing stress on the BPSG/TEOS ofthe lattice portions.

The present disclosure includes methods, apparatuses, and systemsrelated to forming a capacitor using a sacrificial layer. An example ofa method described herein includes forming a pillar on a substratematerial. The pillar includes a number of layers of silicate material, anumber of layers of nitride material, and a sacrificial layer on a topportion of the pillar. The example method further includes depositing acolumn of nitride material between the pillar and an adjacent pillar andremoving the sacrificial layer.

In the following detailed description of the present disclosure,reference is made to the accompanying drawings that form a part hereof,and in which is shown by way of illustration how one or more embodimentsof the disclosure may be practiced. These embodiments are described insufficient detail to enable those of ordinary skill in the art topractice the embodiments of this disclosure, and it is to be understoodthat other embodiments may be utilized and that process, electrical,and/or structural changes may be made without departing from the scopeof the present disclosure. As used herein, “a number of” something canrefer to one or more such things. For example, a number of capacitorscan refer to at least one capacitor.

The figures herein follow a numbering convention in which the firstdigit or digits correspond to the figure number of the drawing and theremaining digits identify an element or component in the drawing.Similar elements or components between different figures may beidentified by the use of similar digits. For example, reference numeral112 may reference element “12” in FIG. 1, and a similar element may bereferenced as 212 in FIG. 2. In some instances, a plurality of similar,but functionally and/or structurally distinguishable, elements orcomponents in the same figure or in different figures may be referencedsequentially with the same element number (e.g., 124-1, 124-2, 124-3,124-4, 124-5 in FIG. 1).

FIG. 1 illustrates a cross-sectional view 100 of a portion of an examplememory device at a particular stage in an example semiconductorfabrication sequence for forming a capacitor using a sacrificial layerin accordance with a number of embodiments of the present disclosure.The example memory device 100 can include a plurality of pillars 109-1,109-2, . . . , 109-N (hereinafter referred to collectively as pluralityof pillars 109). Each of the plurality of pillars 109 can include afirst silicate material 103, shown to have been formed over anunderlying substrate material 101. The substrate material 101 may beformed from various undoped or doped materials on which memory devicematerials may be fabricated. Examples of a relatively inert undopedsubstrate material 101 may include monocrystalline silicon(monosilicon), polycrystalline silicon (polysilicon), and amorphoussilicon, among other possibilities.

The first silicate material 103 may, in a number of embodiments, havebeen formed from a borophosphosilicate glass (BPSG). The BPSG mayinclude a silicon compound doped with various concentrations and/orratios of a boron compound and a phosphorus compound. The siliconcompound may be silicon dioxide (SiO₂), which may be formed by oxidationof silane (SiH₄), among other possibilities. The boron compound may bediboron trioxide (B₂O₃), which may be formed by oxidation of diborane(B₂H₆), among other possibilities. The phosphorus compound may bediphosphorus pentoxide (P₂O₅), which may be formed by oxidation ofphosphine (PH₃), among other possibilities. The silicon, boron, andphosphorus compounds of the BPSG may include various isotopes ofsilicon, boron, and phosphorus, as determined to be appropriate forfunctionality, formation, and/or removal of the first silicate material103, as described herein.

The first silicate material 103 may be originally formed (e.g.,deposited) as a single layer on a surface 110 of the underlyingsubstrate material 101. For example, the first silicate material 103 maybe formed without an opening formed therein from an upper surface of thefirst silicate material 103 to the surface 110 of the underlyingsubstrate material 101. The single layer of the first silicate material103 may, in a number of embodiments, be deposited to a thickness in arange of from around 400 nanometers (nm) to around 750 nm above thesurface 110 of the underlying substrate material 101.

A first nitride material 105 is shown to have been formed over a surfaceof the first silicate material 103 opposite from the underlyingsubstrate material 101. The first nitride material 105 may be formed(e.g., deposited) as a single layer on an upper surface of the firstsilicate material 103. Alternatively, the first nitride material 105 maybe formed (e.g., deposited) as two separate portions (e.g., layers) onthe upper surface of the first silicate material 103. For example, thefirst silicate material 103 may be formed with an opening (such as theopening illustrated between materials 109-1 and 109-2 in FIG. 1,illustrated as pillars in this 2-dimensional format but not necessarilypillars in a 3-dimensional format, for example) formed therein from anupper surface of the first nitride material 105 to an upper surface ofthe first silicate material 103.

The first nitride material 105 may be formed from a nitride materialselected for dielectric or resistance properties. For example, one ormore dielectric and/or resistor nitrides may be selected from boronnitride (BN), silicon nitride (SiN_(X), Si₃N₄), aluminum nitride (AlN),gallium nitride (GN), tantalum nitride (TaN, Ta₂N), titanium nitride(TiN, Ti₂N), and tungsten nitride (WN, W₂N, WN₂), among otherpossibilities, for formation of the first nitride material 105. Thefirst nitride material 105 may, in a number of embodiments, be depositedto a thickness in a range of from around 15 nm to around 30 nm above thesurface of the first silicate material 103.

A second silicate material 106 is shown to have been formed over asurface of the first nitride material 105 opposite from the firstsilicate material 103. The second silicate material 106 may, in a numberof embodiments, be formed from tetraethyl orthosilicate (Si(OC₂H₅)₄),which is also referred to as TEOS. TEOS may be formed as an ethyl esterof orthosilicic acid (Si(OH)₄), among other possibilities.

A second nitride material 108 is shown to have been formed over asurface of the second silicate material 106 opposite from first nitridematerial 105. The second nitride material 108 may be formed (e.g.,deposited) as a single layer on an upper surface of the second silicatematerial 106.

Similar to the first nitride material 105, the second nitride material108 may be formed from a nitride material selected for dielectric orresistance properties. For example, one or more dielectric and/orresistor nitrides may be selected from BN, SiN_(X), Si₃N₄, AlN, GN, TaN,Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, among other possibilities, forformation of the second nitride material 108. In various embodiments,the first nitride material 105 and the second nitride material 108 maybe formed from a same single nitride or a same mixture of nitrides orthe first and second nitride materials 105, 108 each may be formed froma different single nitride or a different mixture of nitrides dependentupon, for example, various uses to which the nitrides may be applied.The second nitride material 108 may, in a number of embodiments, bedeposited to a thickness in a range of from around 80 nm to around 150nm above the surface of the second silicate material 106.

A sacrificial material 112 may be formed over a surface of the secondnitride material 108 opposite from the second silicate material 106. Inat least one embodiment, the sacrificial material 112 may be a thirdnitride material. In at least one embodiment, the sacrificial material112 can be a different nitride material than the second nitride material108. In at least one embodiment, the sacrificial material 112 can be asame nitride material than the second nitride material 108.

Similar to the first nitride material 105 and the second nitridematerial 108, the sacrificial material 112 may be formed from a nitridematerial selected for dielectric or resistance properties. For example,one or more dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the sacrificial material 108. Invarious embodiments, the first nitride material 105, the second nitridematerial 108, and the sacrificial material 112 may be formed from a samesingle nitride or a same mixture of nitrides or the first and secondnitride materials 105, 108 and the sacrificial material 112 each may beformed from a different single nitride or a different mixture ofnitrides dependent upon, for example, various uses to which the nitridesmay be applied. The sacrificial material 112 may, in a number ofembodiments, be deposited to a thickness in a range of from around 80 nmto around 150 nm above the surface of the second nitride material 108.

An etch process (e.g., a first wet etch process or dry etch process) maybe utilized to etch via (e.g., through) the sacrificial material 112,the second nitride material 108, the second silicate material 106, thefirst nitride material 105, and/or the first silicate material 103 toform an opening within the previously listed materials (as isillustrated already between materials 109-1 and 109-2). Performance ofthe etch process may result in formation of an opening within anycombination of the materials 109-1 in order to form a resultant openingthat extends from the upper surface of the sacrificial material 112 tothe surface 110 of the substrate material 101. The resultant opening mayhave a height 122 in a range of from around 8,000 Angstroms (or 800 nm)to around 15,000 Angstroms (or 1,500 nm). Each of the materials cancontribute a particular height to the overall height 122 of thestructure. As an example, the first silicate material 103 can be aheight 124-5, the first nitride material can be a height 124-4, thesecond silicate material 106 can be a height 124-3, the second nitridematerial 108 can be a height 124-2, and the sacrificial layer 112 can bea height 124-1, that, when added together, results in the overall height122.

In some embodiments, the height 124-5 of the first silicate material 103can be one of 4800 Angstroms, 5000 Angstroms, 5300 Angstroms, 5700Angstroms, and/or within a range from 3000-7000 Angstroms. In someembodiments, the height 124-4 of the first nitride material 105 can beone of 100 Angstroms, 200 Angstroms, 300 Angstroms, and/or within arange from 100-500 Angstroms. In some embodiments, the height 124-3 ofthe second silicate material 106 can be one of 4800 Angstroms, 5000Angstroms, 5300 Angstroms, 5700 Angstroms, and/or within a range from3000-7000 Angstroms. In some embodiments, the height 124-2 of the secondnitride material 108 can be one of 200 Angstroms, 400 Angstroms, 800Angstroms, and/or within a range from 200-1500 Angstroms. In someembodiments, the height 124-2 of the sacrificial material 112 can be oneof 200 Angstroms, 400 Angstroms, 700 Angstroms, 800 Angstroms, and/orwithin a range from 200-1500 Angstroms.

In at least one embodiment, the width or diameter of the opening betweenmaterials 109-1 and 109-2 can be within in a range of from around200-600 Angstroms (or 20 to 60 nm) and the height of the opening can bewithin a range of from around 8,000-15,000 Angstroms (800-1,500 nm) andmay result in an aspect ratio (AR) of the height to width being in arange of from around 25:1 to around 50:1 as the etch progresses throughthe first silicate material 103 and approaches the substrate material101.

As the height 122 of the materials 109-1 to 109-N increases, a bendingand/or leaning of the materials 109 can occur. In some embodiments, asupport structure may be formed for the second silicate material 106stacked on the first silicate material 103 adjacent the substratematerial 101 in order to minimize this bending and/or leaning. Thesupport structure may, in a number of embodiments, be formed by forming(e.g., depositing) the first nitride material 105 between the firstsilicate material 103 and the second silicate material 106 and formingthe second nitride material 108 on an opposite surface of the secondsilicate material 106. The first and second nitride materials 105, 108may form the support structure by extending between and connecting(e.g., attaching) to features associated with multiple capacitors (e.g.,as shown and described in connection with FIGS. 4-6) or other structuralelements of the example memory device. A support structure formed assuch may enable a stack of the first and the second silicate materials103, 106 to be maintained in a more static configuration relative toeach other and the underlying substrate material 101 than provided bythe first and the second silicate materials 103, 106 themselves.

However, this support structure may minimize an amount of surface areafor contact with a capacitor, thereby decreasing efficiency of thecapacitor. In order to prevent this, a sacrificial material 112 can beapplied in order to provide a structure for increasing the height of thecapacitor and subsequently being removed in order to increase a surfacearea of contact of the capacitor, as will be described further inassociation with FIGS. 2-6.

FIG. 2 illustrates a cross-sectional view 220 of a portion of an examplememory device at a particular stage in an example fabrication sequencefor formation of a capacitor in association with an opening inaccordance with a number of embodiments of the present disclosure. FIG.2 illustrates a structure of the portion of the example memory device ata stage in time following completion of the fabrication sequencedescribed in connection with FIG. 1.

As described in connection with FIG. 1, a first nitride material 205 maybe formed (e.g., deposited) between the first silicate material 203 andthe second silicate material 206. A second nitride material 208 also maybe formed (e.g., deposited) on a second silicate material 506 and asacrificial material 212 may be formed (e.g., deposited) on the secondnitride material 208. An opening 211-1 between materials 209-1 and 209-2may extend from the substrate material 201 to the sacrificial layer 212.For clarity in the example fabrication sequence, FIG. 2 shows a firstopening 211-1 and a second opening 211-1 in the portion of the examplememory device, although embodiments are not limited to two openings andmay include any number of such openings.

As shown in FIG. 2, a first electrode material 236 has been formed(e.g., deposited) on the surface 210 of the substrate material 201 andon the sidewalls of the openings 211-1 and 211-2. In a number ofembodiments, the first electrode material 236 also may have been formedover the upper surface of the second nitride material 208. As isillustrated in FIG. 2, a capacitor material 216 is shown as having beenformed (e.g., deposited) to fill the openings 211-1, 211-2 from thesubstrate material 201 to a height 222 of the opening 211 at the uppersurface of the second nitride material 208. Each of the materials cancontribute a particular height to the overall height 222 of thestructure. As an example, the first silicate material 203 can be aheight 224-5, the first nitride material can be a height 224-4, thesecond silicate material 206 can be a height 224-3, the second nitridematerial 208 can be a height 224-2, and the sacrificial layer 212 can bea height 224-1, that, when added together, results in the overall height222.

In a number of embodiments, the capacitor material 216 may be depositedto fill the openings 211-1, 211-2 to an upper surface of the firstelectrode material 236. The first electrode material 236 and thecapacitor material 216 may be formed from any conductive materials andto any width (e.g., thickness) usable in association with formation ofan operable capacitor for a semiconductor device.

FIG. 3 illustrates a cross-sectional view 325 of a portion of an examplememory device at a particular stage in the example fabrication sequencefor formation of a capacitor in accordance with a number of embodimentsof the present disclosure. FIG. 3 illustrates a structure of the portionof the example memory device at the particular stage followingcompletion of the example fabrication sequence described in connectionwith FIGS. 1-2.

As shown in FIG. 3, the sacrificial material (e.g., sacrificial material112 in FIGS. 1 and 212 in FIG. 2) has been removed from the portion ofthe example memory device shown in FIG. 2. The sacrificial material maybe removed with (via application of) a solvent that is selective forremoving (e.g., dissolving) the sacrificial material from the memorydevice while not removing (e.g., leaving) other materials such thatthose materials remain in the memory device (such as not removing thefirst silicate material 303, the first nitride material 305, the secondsilicate material 306, and the second nitride material 308). Such aselective solvent may be selected from water (H₂O), methanol (CH₃OH),ethanol (C₂H₅OH), isomers of propanol (C₃H₇OH) such as n-propanol andisopropanol, n-butanol (C₄H₉OH), among other possible alcohols, andsulfuric acid (H₂SO₄), Hydrofluoric acid (HF), Phosphoric Acid (H₃PO₄),Hydrochloric Acid (HCl), Ammonium Hydroxide (NH₄OH), and combinationsthereof, among other possibilities. Removal of the sacrificial materialmay leave empty spaces (e.g., voids) in the structure of the memorydevice that expose a top portion 315 of the first electrode material336, thereby increasing an exposed surface area of the first electrodematerial 336.

In contrast, the application of the selective solvent may leave thecapacitor material 316 having the first electrode material 336 formedover an outer surface thereof remaining in the structure of the memorydevice. In addition, the first silicate material 303, the first nitridematerial 305, the second silicate material 306, and the second nitridematerial 308 may be left remaining following the application of theselective solvent, among other possible components or structuralfeatures that may remain in the structure of the memory device.

As is illustrated in FIG. 3, the first silicate material 303 can be aheight 324-5, the first nitride material can be a height 324-4, thesecond silicate material 306 can be a height 324-3, the second nitridematerial 308 can be a height 324-2, and the sacrificial layer 312 can bea height 324-1, that, when added together, results in the overall height322.

While the example in association with FIG. 3 describes removing thesacrificial material prior to removal of the first silicate material 303and the second silicate material 306, examples are not so limited. In atleast one example, the first silicate material 303 and the secondsilicate material 306 can be removed prior to removal of the sacrificialmaterial (e.g., the process described in association with FIG. 4 may beperformed prior to the process described in association with FIG. 3).

FIG. 4 illustrates a cross-sectional view 430 of a portion of an examplememory device at a particular stage in the example fabrication sequencefor formation of a capacitor in accordance with a number of embodimentsof the present disclosure. FIG. 4 illustrates a structure of the portionof the example memory device at the particular stage followingcompletion of the example fabrication sequence described in connectionwith FIGS. 1-3.

The first silicate material (e.g., BPSG, borosilicate glass (BSG),phosphosilicate glass (PSG), or TEOS) shown at 403 in FIG. 4 and thesecond silicate material (e.g., BPSG, BSG, PSG, or TEOS) shown at 406 inFIG. 4 have been removed from the portion of the example memory device.The first silicate material 403 and the second silicate material 406 maybe removed with (via application of) a solvent that is selective forremoving (e.g., dissolving) the first and second silicate materials fromthe memory device while not removing (e.g., leaving) other materialssuch that those materials remain in the memory device. Such a selectivesolvent may be selected from water (H₂O), methanol (CH₃OH), ethanol(C₂H₅OH), isomers of propanol (C₃H₇OH) such as n-propanol andisopropanol, n-butanol (C₄H₉OH), among other possible alcohols, andsulfuric acid (H₂SO₄), Hydrofluoric acid (HF), Phosphoric Acid (H₃PO₄),Hydrochloric Acid (HCl), Ammonium Hydroxide (NH₄OH), and combinationsthereof, among other possibilities. Removal of the first silicatematerial 403 and the second silicate material 406 may leave empty spaces(e.g., voids) in the structure of the memory device.

In contrast, the application of the selective solvent may leave thecapacitor material 416 having the first electrode material 436 formedover an outer surface thereof remaining in the structure of the memorydevice. In addition, the first nitride material 405 and the secondnitride material 408 may be left remaining following the application ofthe selective solvent, among other possible components or structuralfeatures that may remain in the structure of the memory device. Theremaining first nitride material 405 and the remaining second nitridematerial 408 may function as a capacitor support structure, as describedfurther in connection with FIG. 5, to provide support in view of thevoids in the structure of the memory device.

As is illustrated in FIG. 4, a height 422 of the capacitor material 416can include a height 424-4 and 424-2 of the first nitride material 405and the second nitride material 408 along with heights 424-1, 424-3, and424-5 of the removed sacrificial material, the second silicate material,and the first silicate material, respectively

During at least one of the stages described in association with FIGS.3-4, a portion of the capacitor material 416, along with the firstelectrode material 436 on an upper surface of the second nitridematerial 408, may have been removed (e.g., etched). More of the firstelectrode material 436 may have been formed (e.g., deposited) on uppersurfaces of remaining portions of the capacitor material 416, such thatthe capacitor material 416 is covered on all surfaces with the firstelectrode material 436. An upper surface of the first electrode material436 may, in a number of embodiments, be coplanar with the upper surface409 of the second nitride material 408 such that a height 422 of thecapacitor material 416 covered by the first electrode material 436 maybe the same as the height of the original opening. As an example, theheight 422 of the capacitor material 416 spans the height 424-5 of theremoved first silicate material, the height 424-4 of the first nitridematerial 405, the height 424-3 of the removed second silicate material,the height 424-2 of the second nitride material 408, and the height424-1 of the removed sacrificial material.

FIG. 5 illustrates a cross-sectional view 535 of a portion of an examplememory device at a particular stage in the example fabrication sequencefor formation of a capacitor in accordance with a number of embodimentsof the present disclosure. FIG. 5 illustrates a structure of the portionof the example memory device following completion of the examplefabrication sequence described in connection with FIGS. 1-4.

As shown, a dielectric material 546 has been formed (e.g., deposited) onan outer surface of the first electrode material 536. The dielectricmaterial 546 may, in a number of embodiments, be formed from a surface510 of the substrate material 501 to cover the outer surface, includingan upper surface, of the first electrode material 536.

As is illustrated in FIG. 5, a height 522 of the capacitor material 516can include a height 524-4 and 524-2 of the first nitride material 505and the second nitride material 508 along with heights 524-1, 524-3, and524-5 of the removed sacrificial material, the second silicate material,and the first silicate material, respectively.

FIG. 6 illustrates a cross-sectional view 640 of a portion of an examplememory device at a particular stage in the example fabrication sequencefor formation of a capacitor in accordance with a number of embodimentsof the present disclosure. FIG. 6 illustrates a structure of the portionof the example memory device following completion of the examplefabrication sequence described in connection with FIGS. 1-5.

As shown, the dielectric material 646 has been formed (e.g., deposited)on an outer surface of the first electrode material 636. The dielectricmaterial 646 may, in a number of embodiments, be formed from a surface610 of the substrate material 601 to cover the outer surface, includingan upper surface, of the first electrode material 636. A capacitor 648may be subsequently formed, at least in part, by formation (e.g.,deposition) of a second electrode material 647 on an outer surface ofthe dielectric material 646.

As is illustrated in FIG. 6, a height 622 of the capacitor material 616can include a height 624-4 and 624-2 of the first nitride material 605and the second nitride material 608 along with heights 624-1, 624-3, and624-5 of the removed sacrificial material, the second silicate material,and the first silicate material, respectively.

The portion of the example memory device illustrated in FIG. 6 shows afirst capacitor 648-1 and a second capacitor 648-2 indicated as widthsin the structure and formed as just described. A height 622 of thecapacitors 648-1, 648-2 may be higher than the height of the originalopening due to the dielectric material 646 and second electrode material647 being formed over the first electrode material 636. The examplememory device illustrated in FIG. 6 shows a buffer material 643 that maybe formed around and between the first and second capacitors 648-1,648-2 as electrical insulation. The dielectric material 646, the secondelectrode material 647, and the buffer material 643 may be formed fromany respective dielectric materials, conductive materials, and resistivematerials and to any width (e.g., thickness) usable in association withformation of an operable capacitor for a semiconductor device.

The support structure is formed from the first nitride material 605 andthe second nitride material 608, in addition to the underlying substratematerial 601. The support structure may provide support to the first andsecond capacitors 648-1, 648-2 after the removal of the first and secondsilicate materials 303, 306 has left voids in the structure of thememory device and even after such voids may have been at least partiallyfilled by the buffer material 643. The support structure formed from thefirst and second nitride materials 605, 608 is shown for simplicity tobe attached only to the left side of the first electrode material 636for capacitor 648-1 and the right side of the first electrode material636 for capacitor 648-2. However, the support structure formed from thefirst and second nitride materials 605, 608 also may be on the oppositesides, or may be attached at four position or even surround, the firstand second capacitors 648-1, 648-2. In a number of embodiments, thedielectric material 646, the second electrode material 647, and/or thebuffer material 643 may surround the first electrode material 636 of thecapacitors 648-1, 648-2 except at defined positions where the first andsecond nitride materials 605, 608 of the support structure are attachedto the first electrode material 636.

Formation of the capacitors and a capacitor support structure as justdescribed may enable each of the capacitors to be maintained in a staticconfiguration (e.g., relative to each other and the underlyingmaterial). For example, the capacitor support structure may reduce(e.g., prevent) a possibility of a capacitor bending and/or twistingduring fabrication or use. By including a sacrificial material, asdescribed herein, a particular height of the capacitor can be supportedwithout sacrificing exposure of surface area of the capacitors. Further,the reduction in bending and/or twisting of the capacitors may reduce apossibility of unintended consequences, such as operational failure ofthe semiconductor device, need to replace parts, etc.

Formation of the capacitors and capacitor support structure as justdescribed may be utilized in fabrication of a memory device thatincludes at least one memory cell. Such a memory cell may include atleast one such capacitor, as a data storage element, that is supportedby the capacitor support structure. The memory cell also may include atleast one access device (e.g., transistor) (not shown) that is, or maybe, coupled to the at least one capacitor.

FIG. 7 is a flow diagram of an example method 770 for formation of acapacitor by using a sacrificial material in accordance with a number ofembodiments of the present disclosure. Unless explicitly stated,elements of methods described herein are not constrained to a particularorder or sequence. Additionally, a number of the method embodiments, orelements thereof, described herein may be performed at the same, or atsubstantially the same, point in time.

At block 772, the method 770 may include forming a first silicatematerial on a substrate. The first silicate material may, in a number ofembodiments, have been formed from a borophosphosilicate glass (BPSG).The BPSG may include a silicon compound doped with variousconcentrations and/or ratios of a boron compound and a phosphoruscompound. The silicon compound may be silicon dioxide (SiO₂), which maybe formed by oxidation of silane (SiH₄), among other possibilities. Theboron compound may be diboron trioxide (B₂O₃), which may be formed byoxidation of diborane (B₂H₆), among other possibilities. The phosphoruscompound may be diphosphorus pentoxide (P₂O₅), which may be formed byoxidation of phosphine (PH₃), among other possibilities. The silicon,boron, and phosphorus compounds of the BPSG may include various isotopesof silicon, boron, and phosphorus, as determined to be appropriate forfunctionality, formation, and/or removal of the first silicate material,as described herein.

At block 772, the method 770 may include forming a first nitridematerial on the first silicate material. The first nitride material maybe formed from a nitride material selected for dielectric or resistanceproperties. For example, one or more dielectric and/or resistor nitridesmay be selected from boron nitride (BN), silicon nitride (SiN_(X),Si₃N₄), aluminum nitride (AlN), gallium nitride (GN), tantalum nitride(TaN, Ta₂N), titanium nitride (TiN, Ti₂N), and tungsten nitride (WN,W₂N, WN₂), among other possibilities, for formation of the first nitridematerial. The first nitride material may, in a number of embodiments, bedeposited to a thickness in a range of from around 15 nm to around 30 nmabove the surface of the first silicate material.

At block 773, the method 770 may include forming a second silicatematerial on the first nitride material. The second silicate materialmay, in a number of embodiments, be formed from tetraethyl orthosilicate(Si(OC₂H₅)₄), which is also referred to as TEOS. TEOS may be formed asan ethyl ester of orthosilicic acid (Si(OH)₄), among otherpossibilities.

At block 774, the method 770 may include forming a second nitridematerial on the second silicate material. Similar to the first nitridematerial, the second nitride material may be formed from a nitridematerial selected for dielectric or resistance properties. For example,one or more dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the second nitride material. Invarious embodiments, the first nitride material and the second nitridematerial may be formed from a same single nitride or a same mixture ofnitrides or the first and second nitride materials each may be formedfrom a different single nitride or a different mixture of nitridesdependent upon, for example, various uses to which the nitrides may beapplied. The second nitride material may, in a number of embodiments, bedeposited to a thickness in a range of from around 80 nm to around 150nm above the surface of the second silicate material.

At block 775, the method 770 may include forming a sacrificial materialon the second nitride material. In at least one embodiment, thesacrificial material may be a third nitride material. In at least oneembodiment, the sacrificial material can be a different nitride materialthan the second nitride material. In at least one embodiment, thesacrificial material can be a same nitride material than the secondnitride material. Similar to the first nitride material and the secondnitride material, the sacrificial material may be formed from a nitridematerial selected for dielectric or resistance properties. For example,one or more dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the sacrificial material.

At block 776, the method 770 may include forming a column of capacitormaterial. At block 777, the method 770 may include removing thesacrificial material to expose a top portion of the capacitor material.The method 770 may further include forming the first and second silicatematerials from different silicate materials (e.g., as described inconnection with FIG. 1).

FIG. 8 is a flow diagram of an example method 880 for formation of acapacitor by using a sacrificial material in accordance with a number ofembodiments of the present disclosure. Unless explicitly stated,elements of methods described herein are not constrained to a particularorder or sequence. Additionally, a number of the method embodiments, orelements thereof, described herein may be performed at the same, or atsubstantially the same, point in time.

At block 881, the method 880 may include forming a first silicatematerial on a substrate. The first silicate material may, in a number ofembodiments, have been formed from a borophosphosilicate glass (BPSG).The BPSG may include a silicon compound doped with variousconcentrations and/or ratios of a boron compound and a phosphoruscompound. The silicon compound may be silicon dioxide (SiO₂), which maybe formed by oxidation of silane (SiH₄), among other possibilities. Theboron compound may be diboron trioxide (B₂O₃), which may be formed byoxidation of diborane (B₂H₆), among other possibilities.

At block 882, the method 880 may include forming a first nitridematerial on the first silicate material. The first nitride material maybe formed from a nitride material selected for dielectric or resistanceproperties. For example, one or more dielectric and/or resistor nitridesmay be selected from boron nitride (BN), silicon nitride (SiN_(X),Si₃N₄), aluminum nitride (AlN), gallium nitride (GN), tantalum nitride(TaN, Ta₂N), titanium nitride (TiN, Ti₂N), and tungsten nitride (WN,W₂N, WN₂), among other possibilities, for formation of the first nitridematerial. The first nitride material may, in a number of embodiments, bedeposited to a thickness in a range of from around 15 nm to around 30 nmabove the surface of the first silicate material.

At block 883, the method 880 may include forming a second silicatematerial on the first nitride material. The second silicate materialmay, in a number of embodiments, be formed from tetraethyl orthosilicate(Si(OC₂H₅)₄), which is also referred to as TEOS. TEOS may be formed asan ethyl ester of orthosilicic acid (Si(OH)₄), among otherpossibilities.

At block 884, the method 880 may include forming a second nitridematerial on the second silicate material. Similar to the first nitridematerial, the second nitride material may be formed from a nitridematerial selected for dielectric or resistance properties. For example,one or more dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the second nitride material.

At block 885, the method 880 may include forming a sacrificial materialon the second nitride material. In at least one embodiment, thesacrificial material may be a third nitride material. In at least oneembodiment, the sacrificial material can be a different nitride materialthan the second nitride material. In at least one embodiment, thesacrificial material can be a same nitride material than the secondnitride material. Similar to the first nitride material and the secondnitride material, the sacrificial material may be formed from a nitridematerial selected for dielectric or resistance properties. For example,one or more dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the sacrificial material.

At block 886, the method 880 may include forming a plurality of columnsof capacitor material. As an example, a plurality of columns can beetched out of the first silicate material, the first nitride material,the second silicate material, the second nitride material, and thesacrificial material, resulting in a plurality of openings in thematerials. A capacitor material can be deposited within the etchedopenings, resulting in the plurality of columns of capacitor material.

At block 887, the method 880 may include removing the sacrificialmaterial to expose a top portion of each of the plurality of columns ofcapacitor material. Removing the sacrificial material can increase asurface area of exposure of the plurality of columns of capacitormaterial, thereby increasing the functionality of the capacitor materialand/or a capacitor formed from the capacitor material of a memorydevice.

FIG. 9 is a flow diagram of an example method 990 for formation of acapacitor by using a sacrificial material in accordance with a number ofembodiments of the present disclosure. Unless explicitly stated,elements of methods described herein are not constrained to a particularorder or sequence. Additionally, a number of the method embodiments, orelements thereof, described herein may be performed at the same, or atsubstantially the same, point in time.

At block 991, the method 990 may include forming a borophosphosilicateglass (BPSG) material on a substrate. The BPSG may include a siliconcompound doped with various concentrations and/or ratios of a boroncompound and a phosphorus compound. The silicon compound may be silicondioxide (SiO₂), which may be formed by oxidation of silane (SiH₄), amongother possibilities. The boron compound may be diboron trioxide (B₂O₃),which may be formed by oxidation of diborane (B₂H₆), among otherpossibilities.

At block 992, the method 990 may include forming a first nitridematerial on the BPSG material. The first nitride material may be formedfrom a nitride material selected for dielectric or resistanceproperties. For example, one or more dielectric and/or resistor nitridesmay be selected from boron nitride (BN), silicon nitride (SiN_(X),Si₃N₄), aluminum nitride (AlN), gallium nitride (GN), tantalum nitride(TaN, Ta₂N), titanium nitride (TiN, Ti₂N), and tungsten nitride (WN,W₂N, WN₂), among other possibilities, for formation of the first nitridematerial. The first nitride material may, in a number of embodiments, bedeposited to a thickness in a range of from around 15 nm to around 30 nmabove the surface of the first silicate material.

At block 993, the method 990 may include forming a tetraethylorthosilicate (Si(OC₂H₅)₄) (TEOS) material on the first nitridematerial. TEOS may be formed as an ethyl ester of orthosilicic acid(Si(OH)₄), among other possibilities.

At block 994, the method 990 may include forming a second nitridematerial on the TEOS material. Similar to the first nitride material,the second nitride material may be formed from a nitride materialselected for dielectric or resistance properties. For example, one ormore dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the second nitride material.

At block 995, the method 990 may include forming a sacrificial materialon the second nitride material. In at least one embodiment, thesacrificial material may be a third nitride material. In at least oneembodiment, the sacrificial material can be a different nitride materialthan the second nitride material. In at least one embodiment, thesacrificial material can be a same nitride material than the secondnitride material. Similar to the first nitride material and the secondnitride material, the sacrificial material may be formed from a nitridematerial selected for dielectric or resistance properties. For example,one or more dielectric and/or resistor nitrides may be selected from BN,SiN_(X), Si₃N₄, AlN, GN, TaN, Ta₂N, TiN, Ti₂N), and WN, W₂N, WN₂, amongother possibilities, for formation of the sacrificial material.

At block 996, the method 990 may include forming a column of capacitormaterial. As an example, a column can be etched out of the BPSGmaterial, the first nitride material, the TEOS material, the secondnitride material, and the sacrificial material, resulting in an openingin the materials. A capacitor material can be deposited within theetched opening, resulting in the column of capacitor material.

At block 997, the method 990 may include removing the sacrificialmaterial to expose a top portion of the column of capacitor material.Removing the sacrificial material can increase a surface area ofexposure of the column of capacitor material, thereby increasing thefunctionality of the capacitor material and/or a capacitor formed fromthe capacitor material of a memory device.

In the above detailed description of the present disclosure, referenceis made to the accompanying drawings that form a part hereof, and inwhich is shown by way of illustration how one or more embodiments of thedisclosure may be practiced. These embodiments are described insufficient detail to enable those of ordinary skill in the art topractice the embodiments of this disclosure, and it is to be understoodthat other embodiments may be utilized and that process, electrical,and/or structural changes may be made without departing from the scopeof the present disclosure.

It is to be understood that the terminology used herein is for thepurpose of describing particular embodiments only and is not intended tobe limiting. As used herein, the singular forms “a”, “an”, and “the”include singular and plural referents, unless the context clearlydictates otherwise, as do “a number of”, “at least one”, and “one ormore” (e.g., a number of memory arrays may refer to one or more memoryarrays), whereas a “plurality of” is intended to refer to more than oneof such things. Furthermore, the words “can” and “may” are usedthroughout this application in a permissive sense (i.e., having thepotential to, being able to), not in a mandatory sense (i.e., must). Theterm “include,” and derivations thereof, means “including, but notlimited to”. The terms “coupled” and “coupling” mean to be directly orindirectly connected physically and, unless stated otherwise, caninclude a wireless connection for access to and/or for movement(transmission) of instructions (e.g., control signals, address signals,etc.) and data, as appropriate to the context.

While example embodiments including various combinations andconfigurations of semiconductor materials, underlying materials,structural materials, dielectric materials, capacitor materials,substrate materials, silicate materials, nitride materials, buffermaterials, etch chemistries, etch processes, solvents, memory devices,memory cells, sidewalls of openings and/or trenches, among othermaterials and/or components related to formation of a capacitor using asacrificial material have been illustrated and described herein,embodiments of the present disclosure are not limited to thosecombinations explicitly recited herein. Other combinations andconfigurations of the semiconductor materials, underlying materials,structural materials, dielectric materials, capacitor materials,substrate materials, silicate materials, nitride materials, buffermaterials, etch chemistries, etch processes, solvents, memory devices,memory cells, sidewalls of openings and/or trenches related to use of asacrificial material in formation of a capacitor than those disclosedherein are expressly included within the scope of this disclosure.

Although specific embodiments have been illustrated and describedherein, those of ordinary skill in the art will appreciate that anarrangement calculated to achieve the same results may be substitutedfor the specific embodiments shown. This disclosure is intended to coveradaptations or variations of one or more embodiments of the presentdisclosure. It is to be understood that the above description has beenmade in an illustrative fashion, and not a restrictive one. Combinationof the above embodiments, and other embodiments not specificallydescribed herein will be apparent to those of skill in the art uponreviewing the above description. The scope of the one or moreembodiments of the present disclosure includes other applications inwhich the above structures and processes are used. Therefore, the scopeof one or more embodiments of the present disclosure should bedetermined with reference to the appended claims, along with the fullrange of equivalents to which such claims are entitled.

In the foregoing Detailed Description, some features are groupedtogether in a single embodiment for the purpose of streamlining thedisclosure. This method of disclosure is not to be interpreted asreflecting an intention that the disclosed embodiments of the presentdisclosure have to use more features than are expressly recited in eachclaim. Rather, as the following claims reflect, inventive subject matterlies in less than all features of a single disclosed embodiment. Thus,the following claims are hereby incorporated into the DetailedDescription, with each claim standing on its own as a separateembodiment.

1. A method, comprising: forming a first silicate material on asubstrate; forming a first nitride material on the first silicatematerial; forming a second silicate material on the first nitridematerial; forming a second nitride material on the second silicatematerial; forming a sacrificial material on the second nitride material;forming a column of capacitor material through the first silicatematerial, the first nitride material, the second silicate material, thesecond nitride material, and the sacrificial material, wherein thecolumn of capacitor material is formed to at least a height of theinitially formed sacrificial material; and removing the sacrificialmaterial to expose a side portion towards a top portion of the capacitormaterial.
 2. The method of claim 1, wherein the combination of the firstsilicate material, the first nitride material, the second silicatematerial, the second nitride material, and the sacrificial material isformed to a height of greater than 10,000 Angstroms.
 3. The method ofclaim 2, wherein the first silicate material and the second silicatematerial make up at least 8,600 Angstroms of the height greater than10,000 Angstroms.
 4. The method of claim 1, wherein a height of thefirst silicate material is between 4,000 and 6,000 Angstroms.
 5. Themethod of claim 1, wherein a height of the first nitride material isbetween 100 and 400 Angstroms.
 6. The method of claim 1, wherein aheight of the second silicate material is between 2,000 and 5,000Angstroms.
 7. The method of claim 1, wherein a height of the secondnitride material is between 100 and 1,500 Angstroms.
 8. The method ofclaim 1, wherein a height of the sacrificial material is between 100 and1,500 Angstroms.
 9. The method of claim 1, wherein the first nitridematerial is between the sacrificial material and the first silicatematerial.
 10. The method of claim 1, wherein at least one of the firstsilicate material and the second silicate material comprises one of aborophosphosilicate glass (BPSG) material and a TEOS material.
 11. Themethod of claim 1, wherein the sacrificial material is a nitridematerial.
 12. The method of claim 1, wherein the sacrificial material isa silicate material.
 13. A method, comprising: forming a first silicatematerial on a substrate; forming a first nitride material on the firstsilicate material; forming a second silicate material on the firstnitride material; forming a second nitride material on the secondsilicate material; forming a sacrificial material on the second nitridematerial; depositing a plurality of columns of capacitor material withinthe formed first silicate material, the first nitride material, thesecond silicate material, the second nitride material, and thesacrificial material, wherein the column of capacitor material is formedto a height above a height of the second nitride material; and removingthe sacrificial material to expose a side portion towards a top portionof each of the plurality of columns of capacitor material.
 14. Themethod of claim 13, wherein removing the sacrificial material exposesthe side portion of the column of capacitor material along a width of atleast 700 Angstroms.
 15. The method of claim 13, wherein the firstsilicate material is between the substrate and the first nitridematerial.
 16. The method of claim 13, wherein the second silicatematerial is between the first nitride material and the second nitridematerial.
 17. The method of claim 13 wherein the sacrificial material isdeposited on the second nitride material.
 18. The method of claim 13,wherein removing the sacrificial material comprises etching thesacrificial material.
 19. The method of claim 13, wherein thesacrificial material includes one of TiSiN and TiN.
 20. The method ofclaim 13, further comprising removing the first silicate material andthe second silicate material.
 21. The method of claim 13, wherein: atleast one of the first silicate material and the second silicatematerial is formed from a borophosphosilicate glass (BPSG) materialincluding a silicon compound (SiO₂) doped with a boron compound (B₂O₃)and a phosphorus compound (P₂O₅); at least one of the first silicatematerial and the second silicate material is formed from a tetraethylorthosilicate (TEOS) material.
 22. A method, comprising: forming aborophosphosilicate glass (BPSG) material on a substrate; forming afirst nitride material on the BPSG material; forming a tetraethylorthosilicate (TEOS) material on the first nitride material; forming asecond nitride material on the TEOS material; forming a sacrificialmaterial on the second nitride material; forming a column of capacitormaterial within the formed BPSG material, the first nitride material,the TEOS material, the second nitride material, and the sacrificialmaterial, wherein: the sacrificial material is along a side of thecolumn of capacitor material; and the column of capacitor material isformed to at least a height of the sacrificial material; and removingthe sacrificial material to expose a side portion towards a top portionof the capacitor material.
 23. The method of claim 22, furthercomprising: removing, with a selective solvent, the first silicatematerial and the second silicate material; leaving the capacitormaterial; and leaving the first and second nitride materials as acapacitor support structure.
 24. The method of claim 22, furthercomprising: removing, with a selective solvent, the first silicatematerial and the second silicate material; leaving the capacitormaterial having the first electrode material formed over an outersurface thereof; and leaving the first and second nitride materials as acapacitor support structure.
 25. A portion of a memory device formed bythe method of claim 22, wherein: the memory device comprises at leastone memory cell that includes: at least one capacitor, as a data storageelement, that is supported by the capacitor support structure; and atleast one access device coupled to the at least one capacitor.